Chemistry

Front

What is a chemical symbol?

Back

A chemical symbol is a one or two-letter notation used to represent an element, with at least one capital letter.

Front

What are periods in the periodic table?

Back

Periods are horizontal rows of elements in the periodic table that contain increasing numbers of protons and electrons.

Front

What is a sign of a chemical change?

Back

Signs of a chemical change include change in color, formation of a gas, and formation of a precipitate. Change of state is NOT a sign of a chemical change.

Front

How many elements are in the compound Na2CO3?

Back

There are 3 elements in the compound Na2CO3: Sodium (Na), Carbon (C), and Oxygen (O).

Front

What charge does a neutron have?

Back

A neutron has a neutral charge.

Front

What is the definition of an element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means.

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together.

Front

What is the difference between a physical change and a chemical change?

Back

A physical change alters the form of a substance but not its chemical composition, while a chemical change results in the formation of new substances.

Front

What is the atomic number?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is the role of electrons in an atom?

Back

Electrons are negatively charged particles that orbit the nucleus of an atom and are involved in chemical bonding.